검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 108

        1.
        2024.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigated the perceptions of elementary school preservice teachers in their 4th year at KEducation University, an elementary school teacher-training institution, on the nature of science (NOS). To examine the differences in elementary school preservice teachers’ perceptions of NOS according to their high school career aptitude, we conducted in-depth interviews with two students each in the humanities and social sciences (HS) and natural sciences (NS) based on the subjects that they had taken while attending high school. For this purpose, we used the Views of Nature of Science Form C (VNOS-C) and Views about Scientific Inquiry (VASI) questionnaires, which were reconfigured. The main research results were that the elementary school preservice teachers showed a positivistic perspective on the NOS, validity of scientific knowledge, difference between theory and law, and social and cultural embeddedness of science. However, they had a latest perspective on the tentativeness of scientific knowledge, observation and inference, and the role of imagination and creativity. In particular, there were clear differences in perception between HS and NS teachers in the areas of tentativeness of scientific knowledge and understanding of observation and inference. Based on these research results, educational implications for improving the science education competencies of preservice elementary school teachers were proposed.
        4,300원
        2.
        2024.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Transition metal oxide-based materials have mainly been studied as electrodes for energy storage devices designed to meet essential energy demands. Among transition metal oxide-based materials, hydrated vanadium pentoxide (V2O5 ‧ nH2O), a vanadium oxide material, has demonstrated great electrochemical performance in the electrodes of energy storage devices. Graphene oxide (GO), a carbon-based material with high surface area and high electrical conductivity, has been added to V2O5 ‧ nH2O to compensate for its low electrical conductivity and structural instability. Here, V2O5 ‧ nH2O/GO nanobelts are manufactured with water without adding acid to ensure that the GO is uniformly dispersed, using a microwave-assisted hydrothermal synthesis. The resulting V2O5 ‧ nH2O/GO nanobelts exhibited a high specific capacitance of 206 F/g and more stable cycling performance than V2O5 ‧ nH2O without GO. The drying conditions of the carbon paper electrodes also resulted in more stable cycling performance when conducted at high vacuum and high temperature, compared with low vacuum and room temperature conditions. The improvement in electrochemical performance due to the addition of GO and the drying conditions of carbon paper electrodes indicate their great potential value as electrodes in energy storage devices.
        4,000원
        7.
        2023.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Using a conversation analysis (CA) framework, this study investigated how kindergarten-aged learners took initiative during classroom interactions through multimodal communication resources. Over a thirteen-week period, data was collected from kindergarten English classroom interactions between two male native Englishspeaking teachers (NESTs) and 125 children divided into six classes. The analysis revealed that learners deployed several multimodal communication resources in teacherinitiated sequences, such as finger-folding gestures, hand-raising, and gaze direction. These multimodal resources were employed to retrieve words, acquire turns, provide answers, and impart other kinds of information. The study also showed how very young learners, with limited linguistic resources, were able to attract the teacher’s attention, draw on embodied resources to access a turn, and become active agents influencing the trajectory of both teacher talk and classroom learning. The study concludes with a discussion of learner initiative and multimodal communication resources, and the pedagogical implications carried by the results of the study for classroom interaction with very young learners.
        7,000원
        8.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        안면 부 MRI 검사는 주변 조직에 대한 높은 대조도 와 해상력으로 해부학적 구조 파악과 질환 진단에 이용되고 있다. 최근 검사 시간을 줄이는 동시에 영상의 질을 향상하는 딥러닝이 주목받고 있다. 본 연구는 안면 부 MRI 검사에서 딥러닝 의 유용성을 알아보기 위해 34명의 환자를 대상으로 딥러닝 T2 강조 영상과 고식적인 T2 강조 영상의 축상면, 관상면 영상을 각각 획득하여, 무참조 영상 품질평가 기법인 NIQE와 NIMA를 통하여 정량적 평가하였고, 리커트 4점 척도를 통해 정성적 평가하였다. NIQE 결과에서 딥러닝 T2 강조 영상은 고식적인 T2 강조 영상보다 영상 품질이 우수하였고, NIMA 결과에서는 딥러닝 T2 강조 영상의 축상면은 통계적으로 유의한 차이가 없었고, 딥러닝 T2 강조 영상의 관상면에서는 통계 적으로 유의한 차이가 있었다. 정성적 평가지표에서는 입 인두, 후두 인두에서 질적인 이득이 있었다. 연구 결과를 통해 안면 부 영역 중 무의식적인 움직임이 많은 영역에서 딥러닝을 적용함으로써 고식적인 T2 강조 영상보다 높은 영상의 품질 을 제공하고, 상대적으로 움직임이 덜한 구조물에서도 품질을 유지하며 검사 시간을 2분 이상 단축하여 움직임에 의한 인공 물을 감소시킴으로써 응급 환자 및 비협조 환자의 진단에 유용하게 활용될 것으로 사료 된다.
        4,000원
        9.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Microalgae are a group of photosynthetic microorganisms living in the water. They are in the spotlight as biostimulators and biofertilizers in modern renewable and sustainable agriculture system, attributed to characteristics such as photosynthetic, and metabolism of various industrial wastes and to increase production when treating crops. Scenedesmus sp. CHK0059 is also one of the microalgae with these characteristics, and it has been reported to suppress various diseases in crops and promote the health of vegetables. However, the mode of action that has a positive effect on plants is not yet well understood. This study was designed to focus on the modulation in diversity change of plant microbiota community, which was the result of the preliminary study, and to determine the direct changes in microbial members that trigger the diversity change in the Arabidopsis model system. As a result, there was no change in the phenotype of Arabidopsis and the microbiota community structure in the rhizosphere during the treatment period, but two bacteria genera, Brevibacterium and Pseudomonas, dominance in the rhizosphere was positively correlated with the CHK0059 treatments. And the bacteria had a positive network correlative relationship with 24 other bacteria. Our findings suggest that the application of microalgae was correlated with several microbiota members in the rhizosphere and was expected to affect the microbiota community structure modification in long-term treatment.
        4,000원
        10.
        2022.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Among efforts to improve techniques for the chemical vapor deposition of large-area and high-quality graphene films on transition metal substrates, being able to reliably transfer these atomistic membranes onto the desired substrate is a critical step for various practical uses, such as graphene-based electronic and photonic devices. However, the most used approach, the wet etching transfer process based on the complete etching of metal substrates, remains a great challenge. This is mainly due to the inevitable damage to the graphene, unintentional contamination of the graphene layer, and increased production cost and time. Here, we report the systematic study of an H2 bubbling-assisted transfer technique for graphene films grown on Cu foils, which is nondestructive not only to the graphene film but also to the Cu substrate. Also, we demonstrate the origin of the graphene film tearing phenomenon induced by this H2 bubbling-assisted transfer process. This study reveals that inherent features are produced by rolling Cu foil, which cause a saw-like corrugation in the poly(methyl methacrylate) (PMMA)/graphene stack when it is transferred onto the target substrate after the Cu foil is dissolved. During the PMMA removal stage, the graphene tearing mainly appears at the apexes of the corrugated PMMA/graphene stack, due to weak adhesion to the target substrate. To address this, we have developed a modified heat-press-assisted transfer technique that has much better control of both tearing and the formation of residues in the transferred graphene films.
        4,000원
        11.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        경추 MRI는 연부 조직에 대한 대조도와 분해능이 우수하여 경추 부위의 퇴행성 질환 및 추간공의 협착, 척수염, 추간판 탈출증 등의 신경 질환 검사에 특히 이용되고 있다. 그러나 경추 MRI 검사는 신경 질환에 의한 배경 신호 강도가 증가되어 SNR이 감소하고 이를 보상하기 위해 여기 횟수가 증가되어 검사 시간이 길어지는 단점이 있다. 교통사고나 낙상을 원인으 로 경추 MRI 검사를 진행할 시 검사 시간이 길어 호흡과 질환의 통증에 의한 움직임 등을 최소화해야 최적의 영상을 획득 할 수 있어 환자의 적극적인 협조가 요구되며 적정한 검사 시간의 단축을 통해 인공물이 없는 진단 가능한 영상을 만들어 낼 수 있다. 최근 개발된 SwiftMR 인공지능 소프트웨어는 경추 MRI 검사 시간을 획기적으로 줄일 수 있다. T2 시상면, T2 축상면, T1 시상면, T1 축상면 SwiftMR 영상의 SNR은 목뼈 몸통 223.82 ± 30.82, 척수 273.03 ± 32.38, 가시돌 기 및 가로돌기 378.61 ± 27.64로 측정되었다. 고속스핀 에코 기법의 SNR은 목뼈 몸통 116.51 ± 11.46, 척수 182.1 ± 22.24, 가시돌기 및 가로돌기 227.79 ± 35.55로 측정되었다. 고속스핀에코 기법의 CNR은 182.12 ± 13.24, SwiftMR 기법 CNR은 346.8 ± 41.84로 측정되었다. 고속스핀에코와 SwiftMR 인공지능 소프트웨어가 적용된 영상을 통해 화질 선명도, 신호 강도의 균일성, 목뼈 몸통 주변의 인공물의 관찰자 간 병변에 대한 일치성 평가는 K값이 0.87로 평가되었다. 연구 결과를 통해 경추 MRI 검사에 SwiftMR 인공지능 기법을 적용함으로써 검사 시간을 단축할 수 있으며, 환자의 불편을 최소화하고 진단 가능한 질 좋은 영상 정보를 제공할 수 있을 것으로 사료된다.
        4,000원
        12.
        2022.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to examine the status of the field application of the Science II career electives with the application of the 2015 revised curriculum up to the 3rd year of high school. This study focused on examining high school science teachers’ perceptions of the student-participatory class and process-centered assessment in Science II subjects, which are career-intensive high school science electives. A total of 192 science teachers responded to the survey questionnaire, and 12 teachers participated in interviews. In the in-depth interviews conducted to supplement the survey results, questions were asked about changes in the overall class, the status of student-participatory classes, and changes in the assessment of Science II subjects due to the emphasis on process-centered assessment. The main research results included teachers’perceptions of changes in teaching and assessment methods with the application of the revised curriculum, the degree to which the eight skills used in Science II classes develop the key competencies of science, and the teaching and assessment methods commonly used in Science II classes. Science teachers generally agreed with the purpose and necessity of introducing student-participatory classes and process-centered assessment, which are the core purpose of the 2015 revised curriculum. However, they had difficulties in practice due to the excessive content of Science II subjects. Problems were also encountered with securing objectivity and fairness during assessments and the operation of online science classes due to COVID-19.
        4,000원
        13.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 MRCP 검사에서 대부분 시간이 소요되는 T2 3D 검사 시 CS 기법을 적용해 시간을 단축하고 동시에, CS 계수와 De-noising 계수를 변화시켜 그에 따른 영상 변화에 관하여 연구하고자 하였다. 본 연구는 환자 대신에 3D 프린터를 사용하였으며, 지름 0.55cm인 실리콘 bile duct를 제작하여 실험하였다. 실험 조건은 CS 계수를 1.1, 5, 10, 15, 20, 25로 변화시켰으며, 각각 변화된 CS 계수마다 De-noising 계수를 1, 100, 250, 500, 750, 1000으로 변화시켜 설정된 조건으로 5번씩 검사를 시행하고, 나머지 매개변수는 같게 하여 영상을 획득하였다. 계수 설정 별로 획득된 영상을 SNR, CNR, SSIM 값 순으로 측정하여 비교, 평가하였으며 검사 소요 시간의 변화도 측정하였다. 실험 결과 CS 계수를 기준으로 De-noising을 변화시킨 그룹과 De-noising 계수를 기준으로 CS 계수를 변화시킨 그룹에서 SNR과 CNR 전체적으로 유의하게 감소하였다(p<0.05). 또한, 검사 소요 시간은 CS 계수의 변화에 따라 많이 감소하였다. 특징적으로는 모든 계수 를 변화시킨 그룹에서 De-noising 계수 10, De-noising 계수 100의 그룹이 SNR과 CNR이 가장 높았으며, 구조적인 유사도를 측정하는 SSIM 값도 가장 높은 것으로 나타났다(p<0.05). 결론적으로, 환자의 호흡정지 기법이 가능한 CS 계수 15 이상에서 De-noising 10 또는 De-noising 100의 조합이 영상의 질과 검사 소요 시간에 있어 가장 최선의 계수 설정이며, 특히 CS 계수 20, De-noising 계수 100의 영상이 기준 영상 SNR의 90%, CNR의 97.2%, 구조적 유사성 98.7%로 가장 우수한 설정값으로 나타났다. 본 연구의 CS 계수와 De-noising 계수의 설정은 영상의 질적 수준을 일정 수준 유지하며, MRCP 검사에서 많은 시간이 소요되는 T2 3D sequence의 검사소요 시간을 단축시켜 진단적인 능력은 유지하며 검사 소요 시간을 줄이는 기초자료로 사용 될 것이라고 사료된다.
        4,000원
        14.
        2021.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Chironomids are a large group of invertebrates that live in various aquatic habitats. The distribution range of these invertebrates has become varied due to anthropogenic impacts; as such, their distribution can be used as an indicator of environmental health. Adult chironomids are well known in South Korea; however, the larvae have rarely been studied due to difficulties associated with morphological classification. To address this lack of information, we collected larvae from four important rivers in South Korea and summarized their taxonomic morphological characteristics. The antennae, mandible, and mentum were used for larval taxonomic characterization. In this study, we describe the basic morphological features and key pictorial features of 20 species of chironomids, representing 16 genera.
        4,000원
        15.
        2021.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Learner initiative and very young learner talk have not been fully investigated despite the growing recognition of their importance in English education. Therefore, the present study examined the sequential development of talk-in-interaction observed in an after-school English program in a Korean kindergarten classroom by investigating how children contributed their behaviors to class participation using the methodological framework of conversation analysis. Data was collected from one intact classroom interaction between a native teacher and 28 seven-year-old children. The analysis highlighted a noticeable interactional phenomenon, learner initiative, which was revealed through children’s turn position in the Initiation-Response-Follow-up (IRF) sequence. In particular, this study presented evidence that learner initiative could be displayed through learners’ self-selected turns: initiating repair of the teacher’s previous utterance, asking a question, and displaying knowledge of words. These findings were discussed in relation to the view of learners as active agents through the process of interaction and suggested pedagogical implications of very young learners’ classroom interaction.
        6,100원
        16.
        2021.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Strawberry is one of the major economic crops in the modern agriculture industry worldwide. Fusarium wilt disease, caused by the Fusarium oxysporum f. sp. fragariae (FOF), is known as the most problematic factor in strawberry production. In a previous study, Streptomyces griseus S4-7 was isolated from the strawberry rhizosphere, exhibited an exceptional antifungal activity against the Fusarium wilt pathogen. However, sensitivity variation to S4-7 in the pathogen population was not evaluated. Therefore, we collected the pathogen nationwide and screened the sensitivity of FOF to the biological agent. A total of 96 FOF isolates was tested their sensitivity to the S4-7 and less-sensitive FOF isolates had lower cell wall degradation than the standard FOF strain. However, gene expression level of the cell wall organization (pkc1, gcn5) was not different between the less sensitive and the standard FOF strains. The results suggested that among the FOF population, some isolates may develop tolerance against a biocontrol agent through complex tolerance mechanisms.
        4,000원
        18.
        2021.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to investigate brand slognas that are effective in explaining how brand identity affects consumers. The effect of congruity between brand slogan and self-image (low and high) on attitude to slogans and brands were anaylzed. The moderating effect of self-monitoring (low and high) was also investigated. Survey data from 177 people in their 20s-30s were analyzed through descriptive statistics, exploratory factor analysis, and two-way ANOVA. First, congruity between slogan and self-image had a positive effect on both slogan and brand attitude. In other words, the higher the congruity between slogan and self-image, the more positive the attitude toward the slogan and brand. Second, no interactive effect was found in congruity between slogan and self-image and self-monitoring on slogan attitude; however it was identified for brand attitude. Again, in a group with high congruity between slogan and self-image, attitude toward the brand was more positive when self-monitoring was higher than when it was low. In conclusion, brand slogans that can represent the self-image of highly self-monitoring consumers are effective. In particular, this is meaningful as it has revealed its relationship with the impact of identity self-image congruity and self-monitoring on brand attitudes in fashion brands. These results offer meaningful guidance in determining brand slogans according to consumers’ personal characteristics.
        4,500원
        20.
        2019.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Kiwifruit (Actinidia chinensis Planch.) is an economically important horticultural crop. This study reports a new pathogen of brown leaf spot disease in kiwifruit. Brown leaf spot symptoms were observed on the leaves of cv. Redvita in Jeju, South Korea. The leaf spot diseases appeared as extensive, angular, brown, yellow, white or fused color spots on the leaves. Fungi were isolated and identified as Fusarium tricinctum (Corda) Sacc. based on their morphological and molecular characteristics. Pathogenicity tests were conducted with mycelium and the conidia inoculation. The pathogen was re-isolated from the artificially developed symptoms, and identified as F. tricinctum as Koch’s postulates were confirmed. To our knowledge, this is the first report of the brown leaf spot caused by F. tricinctum on kiwifruit.
        4,000원
        1 2 3 4 5